x86/microcode: Rip out the OLD_INTERFACE

Everything should be using the early initrd loading by now.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220525161232.14924-2-bp@alien8.de

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 762a0b6..f423a2d 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1350,18 +1350,6 @@ config MICROCODE_AMD
          If you select this option, microcode patch loading support for AMD
          processors will be enabled.
 
-config MICROCODE_OLD_INTERFACE
-       bool "Ancient loading interface (DEPRECATED)"
-       default n
-       depends on MICROCODE
-       help
-         DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
-         which was used by userspace tools like iucode_tool and microcode.ctl.
-         It is inadequate because it runs too late to be able to properly
-         load microcode on a machine and it needs special tools. Instead, you
-         should've switched to the early loading method with the initrd or
-         builtin microcode by now: Documentation/x86/microcode.rst
-
 config X86_MSR
        tristate "/dev/cpu/*/msr - Model-specific register support"
        help

diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 239ff5f..b72c413 100644 (file)
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -373,98 +373,6 @@ static int apply_microcode_on_target(int cpu)
        return ret;
 }
 
-#ifdef CONFIG_MICROCODE_OLD_INTERFACE
-static int do_microcode_update(const void __user *buf, size_t size)
-{
-       int error = 0;
-       int cpu;
-
-       for_each_online_cpu(cpu) {
-               struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-               enum ucode_state ustate;
-
-               if (!uci->valid)
-                       continue;
-
-               ustate = microcode_ops->request_microcode_user(cpu, buf, size);
-               if (ustate == UCODE_ERROR) {
-                       error = -1;
-                       break;
-               } else if (ustate == UCODE_NEW) {
-                       apply_microcode_on_target(cpu);
-               }
-       }
-
-       return error;
-}
-
-static int microcode_open(struct inode *inode, struct file *file)
-{
-       return capable(CAP_SYS_RAWIO) ? stream_open(inode, file) : -EPERM;
-}
-
-static ssize_t microcode_write(struct file *file, const char __user *buf,
-                              size_t len, loff_t *ppos)
-{
-       ssize_t ret = -EINVAL;
-       unsigned long nr_pages = totalram_pages();
-
-       if ((len >> PAGE_SHIFT) > nr_pages) {
-               pr_err("too much data (max %ld pages)\n", nr_pages);
-               return ret;
-       }
-
-       cpus_read_lock();
-       mutex_lock(&microcode_mutex);
-
-       if (do_microcode_update(buf, len) == 0)
-               ret = (ssize_t)len;
-
-       if (ret > 0)
-               perf_check_microcode();
-
-       mutex_unlock(&microcode_mutex);
-       cpus_read_unlock();
-
-       return ret;
-}
-
-static const struct file_operations microcode_fops = {
-       .owner                  = THIS_MODULE,
-       .write                  = microcode_write,
-       .open                   = microcode_open,
-       .llseek         = no_llseek,
-};
-
-static struct miscdevice microcode_dev = {
-       .minor                  = MICROCODE_MINOR,
-       .name                   = "microcode",
-       .nodename               = "cpu/microcode",
-       .fops                   = &microcode_fops,
-};
-
-static int __init microcode_dev_init(void)
-{
-       int error;
-
-       error = misc_register(&microcode_dev);
-       if (error) {
-               pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR);
-               return error;
-       }
-
-       return 0;
-}
-
-static void __exit microcode_dev_exit(void)
-{
-       misc_deregister(&microcode_dev);
-}
-#else
-#define microcode_dev_init()   0
-#define microcode_dev_exit()   do { } while (0)
-#endif
-
 /* fake device for request_firmware */
 static struct platform_device  *microcode_pdev;
 
@@ -856,10 +764,6 @@ static int __init microcode_init(void)
                goto out_driver;
        }
 
-       error = microcode_dev_init();
-       if (error)
-               goto out_ucode_group;
-
        register_syscore_ops(&mc_syscore_ops);
        cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",
                                  mc_cpu_starting, NULL);
@@ -870,10 +774,6 @@ static int __init microcode_init(void)
 
        return 0;
 
- out_ucode_group:
-       sysfs_remove_group(&cpu_subsys.dev_root->kobj,
-                          &cpu_root_microcode_group);
-
  out_driver:
        cpus_read_lock();
        mutex_lock(&microcode_mutex);